- Direct monitoring of biocatalytic deacetylation of amino acid substrates by1H NMR reveals fine details of substrate specificity
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Amino acids are key synthetic building blocks that can be prepared in an enantiopure form by biocatalytic methods. We show that thel-selective ornithine deacetylase ArgE catalyses hydrolysis of a wide-range ofN-acyl-amino acid substrates. This activity was revealed by1H NMR spectroscopy that monitored the appearance of the well resolved signal of the acetate product. Furthermore, the assay was used to probe the subtle structural selectivity of the biocatalyst using a substrate that could adopt different rotameric conformations.
- De Cesare, Silvia,McKenna, Catherine A.,Mulholland, Nicholas,Murray, Lorna,Bella, Juraj,Campopiano, Dominic J.
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supporting information
p. 4904 - 4909
(2021/06/16)
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- Bioelectrocatalytic Conversion from N2 to Chiral Amino Acids in a H2/α-Keto Acid Enzymatic Fuel Cell
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Enzymatic electrosynthesis is a promising approach to produce useful chemicals with the requirement of external electrical energy input. Enzymatic fuel cells (EFCs) are devices to convert chemical energy to electrical energy via the oxidation of fuel at the anode and usually the reduction of oxygen or peroxide at the cathode. The integration of enzymatic electrosynthesis with EFC architectures can simultaneously result in self-powered enzymatic electrosynthesis with more valuable usage of electrons to produce high-value-added chemicals. In this study, a H2/α-keto acid EFC was developed for the conversion from chemically inert nitrogen gas to chiral amino acids, powered by H2 oxidation. A highly efficient cathodic reaction cascade was first designed and constructed. Powered by an applied voltage, the cathode supplied enough reducing equivalents to support the NH3 production and NADH recycling catalyzed by nitrogenase and diaphorase. The produced NH3 and NADH were reacted in situ with leucine dehydrogenase (LeuDH) to generate l-norleucine with 2-ketohexanoic acid as the NH3 acceptor. A 92% NH3 conversion ratio and 87.1% Faradaic efficiency were achieved. On this basis, a H2-powered fuel cell with hyper-thermostable hydrogenase (SHI) as the anodic catalyst was combined with the cathodic reaction cascade to form the H2/α-keto acid EFC. After 10 h of reaction, the concentration of l-norleucine achieved 0.36 mM with >99% enantiomeric excess and 82% Faradaic efficiency. From the broad substrate scope and the high enzymatic enantioselectivity of LeuDH, the H2/α-keto acid EFC is an energy-efficient alternative to electrochemically produce chiral amino acids for biotechnology applications.
- Cai, Rong,Chen, Hsiaonung,Chen, Hui,Dong, Fangyuan,Minteer, Shelley D.,Prater, Matthew B.
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supporting information
p. 4028 - 4036
(2020/03/11)
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- SYNTHESIS METHOD FOR L-CYCLIC ALKYL AMINO ACID AND PHARMACEUTICAL COMPOSITION HAVING THEREOF
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A synthesis method for L-cyclic alkyl amino acid and a pharmaceutical composition having the said amino acid are provide in the present disclosure provides. The synthesis method comprises: step A.) preparing a cyclic alkyl keto acid or a cyclic alkyl keto acid salt having Structural Formula (I) or Structural Formula (II), and step B.) mixing the cyclic alkyl keto acid or the cyclic alkyl keto acid salt with ammonium formate, a leucine dehydrogenase, a formate dehydrogenase and a coenzyme NAD+, and carrying out a reductive amination reaction to generate the L-cyclic alkyl amino acid, wherein the Structural Formula (I) is where n1≧1, m1≧0 and the M1 is H or a monovalent cation; the Structural Formula (II) is where n2≧0, m2≧0, the M2 is H or a monovalent cation, an amino acid sequence of the leucine dehydrogenase is SEQ ID No.1.
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- Preparation of (S)-1-cyclopropyl-2-methoxyethanamine by a chemoenzymatic route using leucine dehydrogenase
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(S)-1-Cyclopropyl-2-methoxyethanamine is a key chiral intermediate for the synthesis of a corticotropin-releasing factor-1(CRF-1) receptor antagonist. Resolution of the racemic amine by transaminase from Vibrio fluvalis gave a 38% yield of the S-amine wit
- Parker, William L.,Hanson, Ronald L.,Goldberg, Steven L.,Tully, Thomas P.,Goswami, Animesh
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experimental part
p. 464 - 469
(2012/08/08)
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- Practical syntheses of both enantiomers of cyclopropylglycine and of methyl 2-cyclopropyl-2-N-Boc-iminoacetate
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A facile three-step synthesis of racemic cyclopropylglycine in multigram quantities from inexpensive cyclopropyl methyl ketone has been elaborated. Enzymatic hydrolysis of the N-Boc-protected methyl ester of cyclopropylglycine 9 with the inexpensive enzyme papain from Carica papaya affords both enantiomers of cyclopropylglycine (8) with enantiomeric excesses of 99% or better after deprotection under acidic conditions. Furthermore, the new cyclopropyl group-containing building block methyl 2-cyclopropyl-2-N-Boc-iminoacetate (13) was prepared by N-chlorination and subsequent dehydrochlorination with 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU). Addition of nucleophiles to 13 offers a ready access to an unusual, orthogonally bisprotected α,α-diamino acid derivative and interesting components of rigid peptide backbones.
- Larionov, Oleg V.,De Meijere, Armin
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p. 1071 - 1078
(2007/10/03)
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- INHIBITORS OF CATHEPSIN S
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The present invention provides compounds, compositions and methods for the selective inhibition of cathepsin S. In a preferred aspect, cathepsin S is selectively inhibited in the presence of at least one other cathepsin isozyme. The present invention also provides methods for treating a disease state in a subject by selectively inhibiting cathepsin S.
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Page/Page column 34
(2008/06/13)
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- COMPOUNDS AND COMPOSITIONS AS CATHEPSIN S INHIBITORS
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The invention provides compounds, pharmaceutical compositions comprising such compounds and methods of using such compounds to treat or prevent diseases or disorders associated with the activity of Cathepsin S.
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Page/Page column 25
(2010/02/14)
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- Simple Synthesis of L- and D-Vinylglycine (2-Aminobut-3-enoic Acid) and Related Amino Acid
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A three-step synthesis of vinylglycine 1 has been developed using a readily available starting material (but-3-enenitrile 2), based on the Neber rearrangement of the corresponding N-chloroimidate, and using cheap, convenient reagents.Also described is a convenient optical resolution of the N-tert-butoxycarbonyl derivative by papain-catalysed enantioselective esterifucation in a two-phase system.From the optically active amino acid, related amino acids obtained via epoxidation, dihydroxylation and cyclopropanation have been prepared.The related β,γ-unsaturated amino acids (E)-2-aminopent-3-enoic acid 20 and (E)-2-amino-3-methylpent-3-enoic acid 22 have been synthesised using the same approach.
- Hallinan, Keith O.,Crout, David H. G.,Errington, William
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p. 3537 - 3544
(2007/10/02)
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- Kinetic Resolution of Unnatural and Rarely Occuring Amino Acids: Enantioselective Hydrolysis of N-Acyl Amino Acids Catalyzed by Acylase I
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Acylase I (aminoacylase; N-acylamino-acid amidohydrolase, EC 3.5.1.14, from porcine kidney and the fungus Aspergillus) is broadly applicable enzymatic catalyst for the kinetic resolution of unnatural and rarely occuring α-amino acids.Its enantioselectivity for the hydrolysis of N-acyl L-α-amino acids is nearly absolute, yet it accepts substrates having a wide range of structure and functionality.This paper reports the initial rates of enzyme-catalyzed hydrolysis of over 50 N-acyl amino acids and analogues, the stabilities of the enzymes in aqueous and aqueous/organic solutions, and the effects of different acyl groups and metal ions on the rates of enzymatic hydrolysis.Eleven α-amino and α-methyl α-amino acids were resolved on a 2-29-g scale.Crude L- and D-amino acid products had generally >90percent ee.The utility of resolved amino acids as chiral synthons was illustrated by the preparation of (R)- and (S)-1-butene oxide and the diastereoselective (cis:trans, 7-8:1) iodolactonization of three 2-amino-4-alkenoic acid derivatives.
- Chenault, H. Keith,Dahmer, Juergen,Whitesides, George M.
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p. 6354 - 6364
(2007/10/02)
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